Because light isn't an electric current, fiber is immune to electromagnetic interference (EMI) and radio frequency interference (RFI). You can run a fiber cable right next to a high-voltage power line, a microwave oven, or an MRI machine, and it won't pick up noise. When a communications cable runs parallel and in close proximity to a power cable, these magnetic fields induce unwanted currents—a phenomenon known as inductive coupling—into the sensitive data conductors. This induced noise can. Frequency used to transmitt optical signals is about 1000 times greater than the power frequency. If you can't find a way, make one. A short section of cable next to a power line won't cause big problems, but don't run both through a long conduit right next to each other. An outdoor light will not affect the fiber or the light traveling through it. The first patents on such cables dates.
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